The Serpent Viper 990th is the successor of the successful 989. We have spent a lot of testing and research to improve the 989 platform. We put a lot of emphasis on the flex characteristic since that showed very promising results. On top of that we improved weight, weight distribution and ease of maintenance. Beside all these b=new features we kept 90% of our proven transmission and our excellent shock absorbers.
The ultra-narrow chassis is milled down to allow the lower radio plate as well as improved flex. keeps the improved flex characteristics. The central hole underneath the tank is narrower, as a consequence of the narrower chassis.
The aluminium insert gives the same advantages as in the rear with improved drivetrain efficiency and improved ease of maintenance
But because this insert is eccentric, as is also possible to change the roll-centre as well las using a trailing or leading set-up.
Of course the steering-blocks are still left/right symmetrical and can be used with option1 as well as option2 levers.
The front upper suspension bracket now has an improved design that provides a better placement to avoid camber or caster irregularities by using bushings.
The new lighter 2-speed shaft is 10g (!) lighter and features a super-true mounting of the 18t pulley adapter.
7075 T6 Aluminium 5mm chassis plate
The 5mm aluminium chassis has perfect symmetrical shape for even flex and weight distribution. The ultra-narrow chassis is very light, while it still remains strong in critical places.
The wire type front anti-roll bar is ball raced. It is easy to change and adjust due to the open front end design. The standard wire is 2.5mm and 2 optional thicknesses are available. The pivot ball link system directs the suspension movement to the bar and allows easy tweak adjustment.
The steering blocks are connected to the arms with spring steel 8.5mm pivot balls, which run very smooth and well protected in nylon cups, and are easy to adjust with a 2.5 hex tool.
The long durable front lower wishbones are the open-style arms similar to the 977. An aluminium shock mount plate is screwed onto the lower wishbone. This allows the shock attachment point to be placed further outwards improving shock motion. The front lower arms are mounted to the front brackets with nylon holders. The kit includes 2 versions: in and out. This system also enables quick and easy front drive shaft maintenance.
Of course the 988 closed arms are usable as well
The left and right interchangeable upper arms are mounted with 3 position nylon suspension pin inserts. The 3 position inserts allow camber-change adjustments and are held in place by the anodized aluminium top brackets. Below the top brackets, spacers can be used to change their angle or height. Caster is adjusted with clips on the upper pivot pins. The same clips are also used on the lower pivot pins to change wheelbase.
The black anodized aluminium front axle has Japan made one-way bearings. Spring steel drive cups connect to the long and thin spring-steel drive shafts with CVD system. The ball raced spring steel wheel axles have aluminium quick-change levers. The open front end design allows for very fast and easy removal of the front axle and driveline parts.
The central mounted seervosaver allows easy and fast Ackermann adjustment. The servosaver features a top mounted insert which can be used in 3 positions. Another 2 Ackermann positions are available on the steering blocks.
The rear end construction with aluminium brackets is a very open design, which allows for easy maintenance and cleaning. Dis-assembly requires the removal of only a few screws. Replacing a belt if needed, is a simple task. The eccentric bearing holders on the rear shaft allow adjustment of belt tension. The whole rear end can be removed as one unit from the chassis by removal of only a few screws.
The wire type rear anti-roll bar is ball raced. It is mounted in the rear bearing blocks and is easy to change and adjust. The standard wire is 2.5mm and 2 optional thicknesses are available. The pivot ball link system directs the suspension movement to the bar and allows easy tweak adjustment.
The narrow solid rear axle in Serpent spring steel has a lightweight 9mm wide 48T pulley. Spring steel, CVD type, drive shafts connect the rear shaft to spring steel wheel-axles with aluminium quick-change levers. A very durable and long lasting drivetrain.
The rear floating body mount which is mounted on the up-rights with 2 arms is centered by a carbon-fibre and steel guider. The mount has 4 positions on each side to choose from, depending on body shell used and traction available. The threaded holes on the end of the body mount give the option to add further body-supports.
The upright carries an aluminium insert where the ball bearings of the wheel axle sit. In that way we can achieve the perfect roundness even under load to achieve the least friction of the transmission possible.
Since the upper link is replaced by a suspension arm, we also changed the upper pivot on the upright. It is now super easy to adjust the correct camber.
The central weight bridge is now mounted from underneath and allows for a quick change of the weight.
The weight itself is now fixed using a nylock nut. Bulletproof!
The rear of the chassis has a slot. This will be explained later here. It has to do with adjustable flex. It also carries 2 steel countersunk screws that act as a counterpart of the down-stop screws. This helps to keep the down-stop more accurate and consistent
Talking about flex: we tested a lot and one of the improvements came from lowering the radio plate by 2.5mm. We also changed the shape of it.
The rear of the car is also adjustable regarding the flex. To regular rear end features the proven, one-piece rearplate
The radio-box is completely new. The “backbone” of it is a carbon plate and an aluminium frame.
The aluminium servo mounts are eccentric and can be mounted in 2 ways to adjust them to the brand of servos.
The receiver box is more spacious than the one used in our 988, still it is very compact. It provides enough space even for older type receivers plus the transponder
This new box is mounted to the radio plate in a flexible way in order to not influence the flex of the car.
The extending arm of the frame helps to keep the radio box in the desired position without influencing flex.
By changing the position of the link the amount of toe-gain under compression can be adjusted. The position shown is the “neutral” position.
A large selection of optional parts is available to even further improve performance, speed, weight and looks.
- Promo page
- Facebook page
- Viper 990 Facebook user group
- YouTube video’s
- Online set-up sheets
- Support from distributors, dealers and team drivers worldwide
A nice selection of shirts, sweaters, jackets, caps, bags, tools and decals.
Serpent Viper 990 . Designed by Michael Salven.
With great help from all team-drivers and 989/988 drivers!